Matching support for upgrading of a departmentally shared facility for Electron Paramagnetic Resonance Spectrometry to allow time-domain and multi-dimensional Fourier-transform experiments is requested. The selected spectrometer system is the Bruker ESP-380E-FT-300/00 FT/CW EPR spectrometer and DICE/stochastic-Pulsed-ENDOR accessory. This instrument will be the first of its kind on the Princeton campus and will stimulate new research applications that are currently not accessible here. An initial group of 12 investigators distributed across three academic departments and an industrial laboratory will employ the instrument to extend their research programs in the following primary areas: (1) Structure and function of multi-nuclear metallo-enzymes, (2) molecular probes of the mechanism of Cytochrome P450, (3) Zinc finger proteins and heme protein folding, (4) Probing conformational changes in actin by EPR, (5) Observing and exploiting intermolecular multiplequantum coherences in solution ESR, (6) Selenium-dependent molybdo-pterin enzymes.